Merge branch 'master' of /home/git/concurrency-benchmarks

[c11concurrency-benchmarks.git] / cdschecker_modified_benchmarks / ms-queue-tsan11 / my_queue.cc

diff --git a/cdschecker_modified_benchmarks/ms-queue-tsan11/my_queue.cc b/cdschecker_modified_benchmarks/ms-queue-tsan11/my_queue.cc
new file mode 100755 (executable)
index 0000000..be84c7d
--- /dev/null
+++ b/cdschecker_modified_benchmarks/ms-queue-tsan11/my_queue.cc
@@ -0,0 +1,161 @@
+#include "cds_threads.h"
+#include <stdlib.h>
+#include "librace.h"
+#include "model-assert.h"
+
+#include "my_queue.h"
+
+#define relaxed memory_order_relaxed
+#define release memory_order_release
+#define acquire memory_order_acquire
+
+#define MAX_FREELIST 4 /* Each thread can own up to MAX_FREELIST free nodes */
+#define INITIAL_FREE 2 /* Each thread starts with INITIAL_FREE free nodes */
+
+#define POISON_IDX 0x666
+
+static unsigned int (*free_lists)[MAX_FREELIST];
+
+/* Search this thread's free list for a "new" node */
+static unsigned int new_node()
+{
+       int i;
+       int t = get_thread_num();
+       for (i = 0; i < MAX_FREELIST; i++) {
+               unsigned int node = load_32(&free_lists[t][i]);
+               if (node) {
+                       store_32(&free_lists[t][i], 0);
+                       return node;
+               }
+       }
+       /* free_list is empty? */
+       MODEL_ASSERT(0);
+       return 0;
+}
+
+/* Place this node index back on this thread's free list */
+static void reclaim(unsigned int node)
+{
+       int i;
+       int t = get_thread_num();
+
+       /* Don't reclaim NULL node */
+       MODEL_ASSERT(node);
+
+       for (i = 0; i < MAX_FREELIST; i++) {
+               /* Should never race with our own thread here */
+               unsigned int idx = load_32(&free_lists[t][i]);
+
+               /* Found empty spot in free list */
+               if (idx == 0) {
+                       store_32(&free_lists[t][i], node);
+                       return;
+               }
+       }
+       /* free list is full? */
+       MODEL_ASSERT(0);
+}
+
+void init_queue(queue_t *q, int num_threads)
+{
+       int i, j;
+
+       /* Initialize each thread's free list with INITIAL_FREE pointers */
+       /* The actual nodes are initialized with poison indexes */
+       free_lists = (unsigned (*)[MAX_FREELIST])malloc(num_threads * sizeof(*free_lists));
+       for (i = 0; i < num_threads; i++) {
+               for (j = 0; j < INITIAL_FREE; j++) {
+                       free_lists[i][j] = 2 + i * MAX_FREELIST + j;
+                       atomic_init(&q->nodes[free_lists[i][j]].next, MAKE_POINTER(POISON_IDX, 0));
+               }
+       }
+
+       /* initialize queue */
+       atomic_init(&q->head, MAKE_POINTER(1, 0));
+       atomic_init(&q->tail, MAKE_POINTER(1, 0));
+       atomic_init(&q->nodes[1].next, MAKE_POINTER(0, 0));
+}
+
+void enqueue(queue_t *q, unsigned int val)
+{
+       int success = 0;
+       unsigned int node;
+       pointer tail;
+       pointer next;
+       pointer tmp;
+
+       node = new_node();
+       store_32(&q->nodes[node].value, val);
+       tmp = atomic_load_explicit(&q->nodes[node].next, relaxed);
+       set_ptr(&tmp, 0); // NULL
+       atomic_store_explicit(&q->nodes[node].next, tmp, relaxed);
+
+       while (!success) {
+               tail = atomic_load_explicit(&q->tail, acquire);
+               next = atomic_load_explicit(&q->nodes[get_ptr(tail)].next, acquire);
+               if (tail == atomic_load_explicit(&q->tail, relaxed)) {
+
+                       /* Check for uninitialized 'next' */
+                       MODEL_ASSERT(get_ptr(next) != POISON_IDX);
+
+                       if (get_ptr(next) == 0) { // == NULL
+                               pointer value = MAKE_POINTER(node, get_count(next) + 1);
+                               success = atomic_compare_exchange_strong_explicit(&q->nodes[get_ptr(tail)].next,
+                                               &next, value, release, release);
+                       }
+                       if (!success) {
+                               unsigned int ptr = get_ptr(atomic_load_explicit(&q->nodes[get_ptr(tail)].next, acquire));
+                               pointer value = MAKE_POINTER(ptr,
+                                               get_count(tail) + 1);
+                               atomic_compare_exchange_strong_explicit(&q->tail,
+                                               &tail, value,
+                                               release, release);
+                               thrd_yield();
+                       }
+               }
+       }
+       atomic_compare_exchange_strong_explicit(&q->tail,
+                       &tail,
+                       MAKE_POINTER(node, get_count(tail) + 1),
+                       release, release);
+}
+
+bool dequeue(queue_t *q, unsigned int *retVal)
+{
+       int success = 0;
+       pointer head;
+       pointer tail;
+       pointer next;
+
+       while (!success) {
+               head = atomic_load_explicit(&q->head, acquire);
+               tail = atomic_load_explicit(&q->tail, relaxed);
+               next = atomic_load_explicit(&q->nodes[get_ptr(head)].next, acquire);
+               if (atomic_load_explicit(&q->head, relaxed) == head) {
+                       if (get_ptr(head) == get_ptr(tail)) {
+
+                               /* Check for uninitialized 'next' */
+                               MODEL_ASSERT(get_ptr(next) != POISON_IDX);
+
+                               if (get_ptr(next) == 0) { // NULL
+                                       return false; // NULL
+                               }
+                               atomic_compare_exchange_strong_explicit(&q->tail,
+                                               &tail,
+                                               MAKE_POINTER(get_ptr(next), get_count(tail) + 1),
+                                               release, release);
+                               thrd_yield();
+                       } else {
+                               *retVal = load_32(&q->nodes[get_ptr(next)].value);
+                               success = atomic_compare_exchange_strong_explicit(&q->head,
+                                               &head,
+                                               MAKE_POINTER(get_ptr(next), get_count(head) + 1),
+                                               release, release);
+                               if (!success)
+                                       thrd_yield();
+                       }
+               }
+       }
+       reclaim(get_ptr(head));
+       return true;
+}